Fuel preheating and mixing apparatus for internal combustion engines



' Feb. 11, 1936. w. s. FALCONER FUEL PREHEATING AND MIXING APPARATUS FOR INTERNAL COMBUSTION ENGINES Filed.v Oct. 15', 1934 INVENTORZ WILLmM STunRT Fnmmm Patented Feb. 11, 1936 UNITED STATES PATENT eerie];

FUEL PR-EHEATING AND MIXING APPAQ RATUS roa INTERNAL COMBUSTION ENGINES Australia Application October 13, 1934, Serial No. 748,266 In Australia August 17, 1934 '3 Claims. (Cl.'123-119) This invention relates to improved apparatus for preheating the fuel charge for internal combustion engines, and for diluting the preheated charge with exhaust gases and With humidified oil-charged gas and unburnt fuel from the crank case. The apparatus is applicable for the use of fuels such as distillates and kerosenes. In internal combustion engines of the type operating with the heavier volatile fuels, a certain amount of unburnt fuel escapes past the pistons into the crank case; a proportion of this unburnt fuel escapes in vaporous form through the breather pipe, and the remainder of it dissolves in the sump lubricating oil, thus diluting the sump oil and reducing its lubricating value.

According to the present invention, the charge from the carburetter is passed through a preheating device and then into a mixing chamber where it may be combined with a humidified mixture of unburnt fuel and oil vapour from the engine sump and exhaust system. From the mixing chamber the preheated charge passes into the engine manifold of an internal combustion engine.

The unburnt fuel and oil vapour from the sump and a proportion of unburnt fuel from the exhaust gases are preferably mixed with a regulated amount of air and humidified in a separate mixing cylinder, before they are delivered to the mixing chamber of the preheater for admixture with the carburetted and preheated fuel charge.

The invention is illustrated in the accompanying drawing, in which:--

Fig. 1 is a sectional elevation of the assembled preheater and mixing chamber according to the 35 invention; and

Fig. 2 is a sectional plan of the mixing chamber.

In Fig. 1, l l represents a carburetter of any suitable type which is connected toa section of the exhaust pipe [3. Exhaust gas enters the pipe l3 at l9 and leaves it at 26, in its passage impinging upon and passing round a heating tube l2. Portion of the exhaust gas passes through a supplementary heating tube l fitted transversely through the heating tube l2. The heating tube I5 is bellmouthed at its end It, and it is corrugated at H to increase its heating surface and to augment its heat transmitting capacity by creating turbulence in the gases. The carburetted air charge passes from the carburetter through. the tube l 2 into a neck pipe l8. In its passage through the tube I2, the charge impinges on the corrugated heater tube l5. In the pipe IS, the heated charge passes through a plurality of concentric progressively stepped Venturi tubes I4, the function of which is to produce a high velocity central flow of fuel, and a turbulent lower speed marginal flow. From the pipe E8, the fuel passes to a mixing chamber 2|.

The mixing chamber 2| consists of an outer casting 22 bored at each end at 21 and 21a to fit a rotatable sleeve 24, and a concentric cylinder 28. The sleeve 24 is rotatable about the cylinder 28 which is fixed to the casing 22 by a set screw 29. The sleeve 24 and the cylinder 28 have a number of registering ports 3030 positioned angularly as shown to permit gases to pass in an upward direction from concentric chambers 23-23 into the interior of the cylinder 28, and merge with the flow of gases from the carburetter. By means of a lever 25, operating through a slot 26, the sleeve 24 may be rotated about the cylinder 28 to open or close the ports 30-30.

On one side of the mixing chamber casting 22 is a flange seating 33 having an opening 34, to

which is connected a starting carburetter (not shown) and on another side of the mixing chamber is a flange seating 36 having an opening 43 for a connection through which gas comprising a humidified mixture of unburnt fuel from the exhaust gases, oil vapour and unburnt fuel from the crank case, and a regulated quantity of air, enters the chamber 23. This humidified mixture entering through the opening 43 passes into the chamber 23' and through ports 30' into the cylinder 28 where it combines with the heated fuel charge from the carburetter II. The charge passes through the throttle valve 3! into the intake manifold 32.

When starting up the engine, the throttle of the main carburetter is closed and the lever 25 is moved to the starting position through the slot 26 in the casting 22; the sleeve 24 is thus rotated about the cylinder 28. In this movement the ports 38 opposite the opening 34 are opened and the ports 38 opposite the opening 43 are closed. The suction of the engine is thus directed to the starting carburetter. When the vaporizer has been heated sufllciently, the lever 25 is moved in the opposite direction. The ports 30 opposite the starting carburetter opening 34 are thus closed and the ports 38' opposite the opening 43 are opened for the admission of the diluting gases.

What I claim as my invention and desire to se cure by Letters Patent is:-

1. In a fuel-supplying system for internal comopenings, a stationary tubular member disposed concentrically within said movable member, and having ports adapted to register with the ports of the first member which communicate with one of said openings while the wall of the inner member closes the ports communicating with the other opening, and means for moving the movable member from one communicating position to the other.

2. In a fuel-supplying system for internal combustion engines, a mixing chamber comprising a casing having a pair of inlet openings, a circumferentially movable tubular member mounted in said casing and separating said openings, said member having ports communicating with said openings, a stationary tubular member disposed concentrically within said movable member, and having ports adapted to register with the ports of the first member whic communicate with one of said openings while the wall of the inner member closes the ports communicating with the other opening, means for moving the movable member from one communicating position to the other,

and means for supplying unburned fuel from the exhaust gases to said inner tubular member.

3. In a fuel-supplying system for internal combustion engines, a mixing chamber comprising a casing, a circumferentially movable tubular member mounted in said casing, the walls of said casing and tubular member forming between them a pair of separated chambers, said casing having inlet openings one communicating with each of said chambers, said tubular member having ports communicating with said chambers, a stationary tubular member disposed concentrically within said movable member and having ports adapted to register with the ports of the movable member in communication with one of said chambers while the wall of the inner tubular member closes the ports communicating with the other of said chambers, and means for moving the movable member from one communicating position to the other.

WILLIAM STUARTFALCONER. 

